Question: A thermocouple inserted in a long duct reads 2WF. The duct runs through a furnace that maintains the duct walls at 3WF. Inside the duct a nonabsorbing gas is flowing at such a velocity that the average convective heat transfer coefficient to the thermocouple is 10 Btu/(h ft2 OF). What is the gas temperature at the thermocouple in OF? (Assume that all surfaces are black and that no heat is conducted along the thermocouple leads.)